Spenser Rapone, who graduated in 2016, posted the photo using the hashtag #veteransforkaepernick to show his support for the controversial quarterback, who triggered the NFL’s take-a-knee movement.

Social media erupted: “Wow!!! Open communists in the ranks."

Rapone is now serving as a second lieutenant in the U.S. Army, which told Inside Edition it was "looking into the matter.

"Our uniform represents every corner of our nation and it cannot be used to promote any single ideology."

President Trump continues to rip the NFL for failing to fire players who take a knee during the national anthem.

"The NFL is in a very bad box," the president told reporters before departing the White House for Indiana Wednesday. "You cannot have people disrespecting our national anthem, our flag, our country. That's what they're doing, and in my opinion, the NFL has to change, or you know what's going to happen. Their business is going to go to hell."

He tweeted a video Tuesday of the world's fastest man, Usain Bolt, stopping a TV interview at the 2012 Olympics when the "Star-Spangled Banner" was played.